Advanced heart failure and nocturnal hypoxaemia due to central sleep apnoea are associated with increased serum erythropoietin.

AIMS: Central sleep apnoea (CSA) and increased serum erythropoietin (EPO) concentration have each been associated with adverse prognosis in heart failure (HF) patients. The aim of this study was to examine the relationship between nocturnal hypoxaemia due to CSA and the serum EPO concentration in patients with HF. METHODS AND RESULTS: Heart failure subjects (n = 33) and healthy controls (n = 18) underwent polysomnography (PSG) for diagnosis of CSA and identification and quantification of hypoxaemia. Blood collection for measurement of EPO was performed immediately post-PSG. For the analysis, HF subjects were dichotomized into subgroups defined by the presence or absence of CSA and by HF severity. Multivariate analyses were performed to evaluate the relationships of hypoxaemia and advanced HF to EPO concentration. Mean EPO concentration was 62% higher for HF subjects with CSA than for healthy controls (P = 0.004). The magnitude of nocturnal hypoxaemia was significantly and positively related to EPO concentration (r = 0.45, P = 0.02). Advanced HF was also significantly and positively related to EPO concentration (r = 0.43, P = 0.02). On multivariate analysis, the presence of combined nocturnal hypoxaemia and advanced HF yielded greater correlation to EPO concentration than either factor alone (r = 0.57, P = 0.04 and P = 0.05, respectively). Linear regression demonstrated that the combination of New York Heart Association Class and CSA was strongly associated with EPO concentration (P < 0.0001). CONCLUSION: In non-anaemic HF patients, advanced HF and hypoxaemia due to CSA may each be independently associated with increased serum EPO concentration.

Long-term prognostic significance of elevated cardiac troponin levels in critically ill patients with acute gastrointestinal bleeding.

BACKGROUND: Elevations in troponin level have prognostic importance in critically ill patients, including those with gastrointestinal (GI) bleeding. However, there are no data addressing the independent association of troponin levels and mortality, adjusted for the severity of the underlying disease, in patients with GI bleeding. OBJECTIVE: This study was designed to determine whether troponin T elevations are independently associated with in-hospital, short-term (30 days), and long-term mortality in medical intensive care unit patients with GI bleeding after adjusting for the severity of disease measured by the Acute Physiology, Age, and Chronic Health Evaluation score prognostic system. DESIGN: Retrospective study. SETTING: We examined the Acute Physiology, Age, and Chronic Health Evaluation III database and cardiac troponin T levels from patients consecutively admitted to the medical intensive care unit at Mayo Clinic, Rochester, MN, with acute GI bleeding. PATIENTS: Between August 2000 and July 2005, 1076 patients with acute GI bleeding consecutively admitted to the medical intensive care units. MEASUREMENTS: In-hospital, short-term (30 days), and long-term all-cause mortality. RESULTS: During hospitalization, 8.0% of deaths occurred in patients with troponin T < 0.01% and 11.9% with troponin T > or = 0.01 (p = 0.083). At 30 days, mortality was 10.1% and 18.8% in patients without and with elevations of troponins, respectively (p < 0.001). The Kaplan-Meier expected probability of survival at 1-, 2-, and 3-yr follow-up was 54.2%, 40.8%, and 30.4% with troponin T > or = 0.01 microg/L and 78.3%, 69.3%, and 61.5% with troponin T < 0.01 microg/L (p < 0.001). After adjustment for severity of disease and baseline characteristics, cardiac troponin levels were associated only with long-term mortality (p < 0.001). LIMITATIONS: This is a retrospective, single-center study which included only patients in whom troponin level was determined upon admission. CONCLUSIONS: In patients with GI bleeding severe enough to require admission to the medical intensive care unit, admission troponin T elevations are associated with long-term but not short-term mortality.

Elevated cardiac troponin is an independent risk factor for short- and long-term mortality in medical intensive care unit patients.

BACKGROUND: Troponin elevations are common in critically ill patients. Whether they are predictors of mortality independent of the severity of the underlying disease is unclear. OBJECTIVE: To determine whether troponin elevations predict in-hospital, short-term, and long-term mortality in medical intensive care unit patients independent of the severity of the underlying disease as measured by Acute Physiology and Chronic Health Evaluation III prognostic system. DESIGN: Retrospective study. SETTING: We examined the Acute Physiology and Chronic Health Evaluation III database and cardiac troponin T levels of medical intensive care unit patients at Mayo Clinic, Rochester, MN. PATIENTS: In all, 1,657 patients consecutively admitted to medical intensive care units between August 2000 and December 2001. MEASUREMENTS: In-hospital, short-term (30-day), and long-term all-cause mortality. RESULTS: During hospitalization, 12.5% of patients with a cardiac troponin T < 0.01 microg/L suffered deaths compared with 29.5% among those with cardiac troponin T > or = 0.01 microg/L (p < .001). At 30 days, mortality was 13.7% without and 34.6% with elevations (p < .001). The expected probability of survival at 1-, 2-, and 3-yr follow-up was 43.7%, 33.8%, and 25.7% among patients with cardiac troponin T > or = 0.01 microg/L and 75.3%, 67.6%, and 62.9% in those with cardiac troponin T < 0.01 microg/L, respectively (p < .001). After adjustment for the severity of disease and baseline characteristics, cardiac troponin levels were still associated with in-hospital, short-term, and long-term mortality (p = .006, p = .007, and p = .001, respectively). LIMITATIONS: This is a single-site retrospective study that included only patients in whom a troponin level was obtained on admission. CONCLUSIONS: In medical intensive care unit patients, admission troponin levels are independently associated with short- and long-term mortality, even after adjustment for severity of disease.